Julian the Apostate

Julian the Apostate (332-26 June 363) was Roman emperor from 360 to 363, succeeding Constantius II and preceding Jovian. Julian seized power without a civil war, as his half-brother Constantius died while marching to meet Julian in battle; Julian would be slain at the Battle of Ctesiphon by the Sassanids in 363.

Biography
By the 4th century CE, the Roman Empire could only be governed and defended by dividing imperial power between several emperors, each with regional responsibilities. Flavius Claudius Julianus, a fresh young scion of the reigning imperial family, was declared Caesar (junior emperor) in Gaul in 355.

Julian faced an emergency on the Rhine frontier, where Germanic tribes, the Alemanni, were raiding deep into Roman territory. During 356-359, he led a series of punitive expeditons against them. When the Alemannic king, Chnodomarius, confronted him with a large army of confederate tribes at Argentoratum (present-day Strasbourg) in 357, he carried off a hard-won victory against the numerical odds.

Julian was proclaimed Augustus (senior emperor) in 360 by his men, who liften him up on their shields. Fortunately, the ruling emperor, Constantius II, died before Julian was obliged to uphold his claim by civil war. Sole ruler of the empire, in 363 he launched a campaign agaisnt the Sasanian Shapur II, invading Persia with an army of over 80,000 and advancing to the capital, Ctesiphon. He was forced to withdraw and was killed fighting off enemy skirmishers.